<h3>Preconfigured arrays</h3>
<p>
Both translated and untranslated values are available. The date_week_days_ordered()
function will shift an array of week day names so it starts with the site's
first day of the week, otherwise the weekday names start with Sunday as the first
value, the expected order for many php and sql functions.
</p>
<ul style="color: rgb(0, 0, 187);">
<li>
date_month_names();
</li><li>
date_month_names_abbr();
</li><li>
date_month_names_untranslated();
</li><li>
date_week_days();
</li><li>
date_week_days_abbr();
</li><li>
date_week_days_untranslated();
</li><li>
date_week_days_ordered();
</li><li>
date_years();
</li><li>
date_hours();
</li><li>
date_minutes();
</li><li>
date_seconds();
</li><li>
date_timezone_names();
</li><li>
date_ampm();
</li>
</ul>

<h3>Miscellaneous date manipulation functions </h3>
<p>
Pre-defined constants and functions that will handle pre-1970 and post-2038 
dates in both PHP 4 and PHP 5, in any OS. Dates can be converted from one 
type to another and date parts can be extracted from any date type.
</p>
<ul style="color: rgb(0, 0, 187);">
<li>
DATE_DATETIME
</li><li>
DATE_ISO
</li><li>
DATE_UNIX
</li><li>
DATE_ARRAY
</li><li>
DATE_OBJECT
</li><li>
DATE_ICAL
</li><li>
date_convert()
</li><li>
date_is_valid();
</li><li>
date_part_is_valid();
</li><li>
date_part_extract();
</li>
</ul>

<h3>Date calculation and navigation</h3>
<p>
date_diff() will find the time difference between any two days, measured
in seconds, minutes, hours, days, months, weeks, or years.
</p>

<ul style="color: rgb(0, 0, 187);">
<li>
date_days_in_month();
</li><li>
date_days_in_year();
</li><li>
date_weeks_in_year();
</li><li>
date_last_day_of_month();
</li><li>
date_day_of_week();
</li><li>
date_day_of_week_name();
</li><li>
date_diff();
</li>
</ul>

<h3>Date regex and format helpers </h3>
<p>
Pre-defined constants, an array of date format strings and their 
equivalent regex strings.
</p>
<p>
DATE_REGEX_LOOSE is a very loose regex that will pull date parts out
of an ISO date with or without separators, using either 'T' or a space
to separate date and time, and with or without time.
</p>
<p>
date_format_date() is similar to format_date(), except it takes a 
date object instead of a timestamp as the first parameter.
</p>

<ul style="color: rgb(0, 0, 187);">
<li>
DATE_FORMAT_ISO
</li><li>
DATE_FORMAT_DATETIME
</li><li>
DATE_FORMAT_UNIX
</li><li>
DATE_FORMAT_ICAL
</li><li>

DATE_REGEX_ISO
</li><li>
DATE_REGEX_DATETIME
</li><li>
DATE_REGEX_LOOSE
</li><li>

date_format_date();
</li><li>
date_t()
</li><li>
date_short_formats();
</li><li>
date_medium_formats();
</li><li>
date_long_formats();
</li><li>
date_format_patterns();
</li>
</ul>
